[ARM] Pass subtarget feature "+no-movt" instead of passing backend option

"-arm-use-movt=0".
        
This change is needed since backend options do not make it to the backend
when doing LTO and are not capable of changing the behavior of code-gen
passes on a per-function basis.

rdar://problem/21529937

Differential Revision: http://reviews.llvm.org/D11025

llvm-svn: 242368

1 files changed, 4 insertions, 4 deletions

diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 8c11992f1f8..89e3987170b 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -718,6 +718,10 @@ static void getARMTargetFeatures(const Driver &D, const llvm::Triple &Triple,
   } else if (KernelOrKext && (!Triple.isiOS() || Triple.isOSVersionLT(6))) {
       Features.push_back("+long-calls");
   }
+
+  // The kext linker doesn't know how to deal with movw/movt.
+  if (KernelOrKext)
+    Features.push_back("+no-movt");
 }
 
 void Clang::AddARMTargetArgs(const ArgList &Args, ArgStringList &CmdArgs,
@@ -793,10 +797,6 @@ void Clang::AddARMTargetArgs(const ArgList &Args, ArgStringList &CmdArgs,
   if (KernelOrKext) {
     CmdArgs.push_back("-backend-option");
     CmdArgs.push_back("-arm-strict-align");
-
-    // The kext linker doesn't know how to deal with movw/movt.
-    CmdArgs.push_back("-backend-option");
-    CmdArgs.push_back("-arm-use-movt=0");
   }
 
   // -mkernel implies -mstrict-align; don't add the redundant option.